How many hydrogen atoms are in 8.90 mol of ammonium sulfide?

The number of hydrogen atoms in 8.90 mol of ammonium sulfide is  4.28×10²⁵ atoms.

This is referred to as a proportionality factor which tells us about the number of constituent particles in a sample. The constant is  6.02ₓ 10²³.

Ammonium sulfide which is denoted as (NH4)₂S has 2 nitrogen, 8 hydrogen and 2 sulfur atoms present.

We were told that the amount of ammonium sulfide is 8.90mol.

Number of hydrogen atoms =  8/1 × 8.9 mol= 71.2 moles of H₂.

The number of Hydrogen atoms in  8.90 mol of ammonium sulfide is 71.2 moles ˣ 6.02ˣ 10²³ = 4.28 ˣ10²⁵ atoms.

Read more about Avogadro's constant here link

if the temperature drops and becomes cool

then the atmosphere can be freezing as the water vapor in the air is at maximum (100%) and can be severely cold

also can be snowing lightly as the moisture in the air will start to solidify

and btw this is not chemistry but